The arrangement of the tissue systems and histology of Ihe stem and tendril of Parthenocissus tricuspidata(Sieb. & Zucc.) Planclk have been studied. The arrangement of the tissue systems in the stem is fundamentally the same as that in both staik and holdfast of the tendril. The stem possesses a rather large amount of ground tissue in comparison with other tissues. The tendril stalk has a less amount of living cells, but a larger amount of xylem. The xjrlem is reduced in the holdfast. The peculiar development of the epidermal cells on the attached surface of the holdfast has also been described. Each epidermal cell on the attached surface of the holdfast elongates and undergoes cell divisions to become a hair-like structure after it comes in contact with a substrate. Other cellular changes also occur in these epidermal cells. INTRODUCTION